1. Field of the Disclosure
This disclosure relates generally to arrangements and related methods for protecting oilfield downhole tools from mechanical wear.
2. Background of the Art
To obtain hydrocarbons such as oil and gas, boreholes or wellbores are drilled by rotating a drill bit attached to the bottom of a drilling assembly (also referred to herein as a “Bottom Hole Assembly” or (“BHA”). The drilling assembly is attached to tubing, which is usually either a jointed rigid pipe or flexible spoolable tubing commonly referred to in the art as “coiled tubing.” The string comprising the tubing and the drilling assembly is usually referred to as the “drill string.” When jointed pipe is utilized as the tubing, the drill bit is rotated by rotating the jointed pipe from the surface and/or by a mud motor contained in the drilling assembly. In the case of a coiled tubing, the drill bit is rotated by the mud motor. During drilling, a drilling fluid (also referred to as the “mud”) is supplied under pressure into the tubing. The drilling fluid passes through the drilling assembly and then discharges at the drill bit bottom. The drilling fluid provides lubrication to the drill bit and carries to the surface rock pieces disintegrated by the drill bit in drilling the wellbore. The mud motor is rotated by the drilling fluid passing through the drilling assembly. A drive shaft connected to the motor and the drill bit rotates the drill bit.
During wellbore operations, downhole tools with sensitive outer parts and/or equipment can be subjected to mechanical influences, such as abrasion, chipping and cuttings and chemical influences resulting from a direct contact with the mud flow. Prior to operation, downhole how tools may be subjected to electromagnetic radiation coming from tools storage and transportation on the ground. The present disclosure addresses the need to protect these sensitive parts and equipment.